If you are using Sharepoint 2007 to manage and display your reports then there is a big chance you may be using Reporting Services in Sharepoint Integrated mode. You may have noticed that reports run slower in Sharepoint integrated mode as compared to native mode. This is because of the calls to Sharepoint object model in integrated mode. To improve the performace Microsoft has released some optimizations in Service Pack 3 of SQL Server 2005 which reduces the number of calls to object model and increases the overall response time and performace.
Happy New Year to all readers and best wishes for 2009!